When a character's trait states they can start the game with X or Y do you have to note that during force construction, or do you get the option to choose before the game starts if you have both on your sideline?

For instance Trader:





"Bearer of an Infinity Gem
Trader starts the game with any one [ABPaI] Infinity Gem equipped."

None of the equipment should ever technically be on your Sideline as they come from outside the game.

So, you can choose differently at the beginning of each round in a tournament (with a character like Possessor who can just equip any of the Gems).

This is good, because you can give somebody like Possessor a gem based on the team your opponent is running.

If the objects aren't on the sideline, are they considered part of the force for characters with this ability:

"I SENSE A GREATER CHALLENGE: At the beginning of the game, if an opponent's force includes an additional game element, heal Possessor 1 click past his starting line to click #0. (Current additional game elements are: ID cards, Equipment, Special Terrain, and Locations.)"

Objects that come from outside the game are not part of that force while they remain there (outside of the game).

However, in the case of characters that can begin the game equipped, they will start the game with that equipment and so the timing should result in opposing Elders getting the bonus click.

If you have some way to bring them from outside the game later then the window for the Elders would have passed.

"I SENSE A GREATER CHALLENGE" checks at the beginning of the game rather the during force construction.
So the Trader will have the gauntlet/gem equipped when "I SENSE A GREATER CHALLENGE" checks.

Stupid question along those lines... if you pay for a gem but you face a figure with "I sense a greater challenge" trait, can you choose to not equip one so they don't turn to click 0?

Not unless it says 'may', which the ones I checked don't.

This question on items came for me last night. I found rules about it after coming here.

Comprehensive rulebook, pg 5:

“STARTS THE GAME” TRIGGERED EFFECTS
Some game effects trigger when the character “starts the game”. This occurs when a character is first placed onto the map: during game setup, from outside the game (usually by being generated), or from the Sideline.

If I have two of the same characters, can they have the same gem... example 2 astronomers 2 power gems?

Yep. Objects are unique when they're on your force, but from outside the game you're super green.

Sweet!! Thanks!!